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ATORIC V0.9 (October 1998)
--------------------------

PaCifiST<=0.48-User: Please start ATORIC from a disc! On a mounted hard
disc directory, ATORIC will not find its file. Reason is the wrong
interpretation of PaCifiST's file attributes.


Hello, ORIC-Fan!
Here it is, a new version of ATORIC for the ATARI ST/TT/Falcon
series of computers. Perhaps it will also run on more powerful
machines like the HADES or the MILAN (in a "GEM" window, even
under MultiTOS..).

You'll need about 400kB of free RAM for ATORIC, most of it in the
FAST-RAM region (if you have FAST-RAM).

WHAT IS AN ORIC?
----------------
If you don't know that, you'll probably have not much fun with
ATORIC..
The ORIC computers were quite popular around the Mid-1980ies,
especially in England and France. Two models, the ORIC-1 and the
ATMOS were sold in large quantities. Of course, later there were
advanced "ORIC compatibles" like the TELESTRAT or the STRATOS
but I don't know too much about them.
Hardware description:
CPU: NMOS 6502 8-bit microprocessor, 1MHz clock
RAM: 64kByte (48kByte usable without additional hardware)
ROM: 16kByte
Display: TV compatible, 240x228 Pixel at 8 colors,
just let's say: MINITEL/VIDEOTEXT compatible
Keyboard: Conventional (ATMOS) or funny but very usable (ORIC-1)
Cassette interface: 2400 Baud
Sound chip: AY3-8910 (yeah, Atari also used that one for the ST)
Also, there were different floppy disc drive systems (MICRODISK,
JASMIN) available (emulated by ATORIC up to now is only the
"read-only MICRODISK").


HOW TO SET UP ATORIC
--------------------
Get an editor (if you don't have one, use the supplied ED_E.PRG),
load ATORIC.CNF and read the comments carefully before you change
any parameter!
REZ=0 Auto-detection of graphics (ST,TT,Falcon)
REZ=1 GEM window (TT,Falcon - 16cols only, ATARI-bitmap)
REZ=2 ST-LOW or ST-MONOCHROME
REZ=20000 TT mode (320x480 at 256 Farben)
REZ=30000 Falcon mode (320x256 at 16 Farben)
REZ=40000 VGA mode (>=640*480 at 256 Farben)
Runs e.g. on some Apples (MagicMac).
("packed pixels")!
ST_OVERSCAN= Overscan for the plain ST ?
Usually doesn't work on emulators - but:
** ATARI ST OWNERS: SET ST_OVERSCAN to -1 !! **

SOUND_EMU= Set it to zero if you are using some
newer Hardware NOT containing the Atari
soundchip. Too bad, an ORIC without sound;
but access to that memory locations make
some PowerPC-Apples freeze their system :-(
FILES= The directory where to find the TAPE files
INSTRUCTIONS= number of 6502 instructions between each
interrupt test
ROM= Directory of the ROM files
DISKSTATION= Directory of the Disk files
PRINTER= where to print to (PRN: or some filename).
KEYBOARD= filename to get first chars from (like "welcome to ATORIC")
KBDCHECKRATE= how often to examine the keyboard buffer
KBDSCANCLR= how often to examine the keyboard buffer (for games)
YZ_TURN=
YZ_SCANTURN= swap Y and Z keys for german Ataris?
DISP_LOREZ= Fill 2-pixel-spaces between chars in text mode?
LINESVBL= screen refresh in lines per VBL. BE CAREFUL!!!!
GEMDISPRATE= time constant for GEM mode (too slow anyway)
GEMINVCPY= invert colors for GEM mode?

If you don't have a standard ST (color monitor or SM124), a
standard TT with VGA monitor or a standard Falcon, you'll
probably have to use the GEM resolution (REZ=1). This one only
works only at 16 colors and with Atari bitmap layout.
Another possibility is the VGA mode:
It requires 256 colors at 640*480 or better resolution
and it requires "packed pixels" - the common format for
most "modern" VGA cards.


HOW TO LOAD A PROGRAM
---------------------
Just type in ORIC Basic:
CLOAD""
and specify the file in the file selector box. If you know that
your file e.g. has the name "DEFENDER", type CLOAD"DEFENDER" (16
chars are allowed)

If you are using the disc emulation and have a "disc file",
use the HELP key to enter the emulator's menu, push the key '5'
to see the disc menu, click on the filename of the "disc file"
and select your file. Type DIR or !DIR to read the contents of that
disc - if it is for another ORIC DOS, just reboot with keypad '/' key..

To check the speed of the emulation, type
10 FOR I=1 TO 10000:NEXT
20 EXPLODE
RUN
(ORIC ATMOS: 15 sec,
Falcon030: 36 sec,
TT030: 25 sec,
520ST+: 127 sec.
Milan (68040): 5 sec., 20 sec. without Cache
Apple Performa 6300, 100MHz 603e: 17 sec.
)

Well, it is not easy to emulate an 6502 processor on an 68000..
The 6502 at 1MHz is often comparable fast as a 4MHz Z80 or a
5MHz 8086 as long as you deal with 8 bit data! Some people even
think that the 6502 is a prototype of the "RISC" processor idea!
Furthermore, the 68000 design is quite different (68000:
16-bit-word=high_byte low_byte at even address; 6502:
16-bit-word=low_byte high_byte at any address).
The Apple Performa meets the worst case: First, its PowerPC processor
has to emulate a 68020. This "68020" then emulates the 6502..
Furthermore, the VGA screen emulation costs a lot of time..


HISTORY
-------
V0.9:
* CRC checksum implemented..
* VGA graphics mode introduced for "modern" Atari-compatibles
V0.8:
* Write accesses to Microdisc enabled.
If you don't wont that, just mark the disc file (under TOS)
as "read only"
* a track buffer reduces read accesses to the disc file. So it
is now less annoying to read disc files from discs..
* Telestrat emulation runs (incredibly slow). Sometimes it even
recognizes keyboard input
* RANDOS works. Thanks again to Fabrice Frances!
* SEDORIC and XLDOS patch now has a proper name
V0.7:
* Falcon030 Overscan for RGB monitor re-introduced..
* read-only MICRODISK emulation (that was not too easy..)
* Telestrat emulation (incredibly slow)
The two new features are based on a technique called
"bank switching", the only way to get over the 64kByte barrier
on the 6502 or Z80 microprocessors. It means that a part
of the memory is exchanged by hardware. ATORIC simulates
that by software-moving of that memory - really very slow
but it doesn't further slow down the 6502 emulation.
Drawback: The function-key support of SEDORIC and XLDOS has
to be removed - otherwise you could type a char every three
seconds on the 68030/16.. (ATORIC.CNF: PATCHSEDATMOS=1)
And the Telestrat emulation is that slow because of the
slow bank-switching.
V0.6:
ATORIC was ported to the PureC/PureASM platform. Due to the
(my) need for advanced features like file selector boxes,
I decided to leave the Omikron.Assembler (TurboASS) platform.
Therefore, ATORIC 0.6 is a little bit slower than the former
versions but has more features:
* Enhanced keyboard emulation - some games will work now (DEFENDER)
* Now the Atari TT is really supported (sorry, I claimed
that since V0.1 - nobody complained !?)
Too bad that there is no 320x(>=224)x16col. screen mode on TT!
* slow&dirty "GEM" display mode for VERY fast computers..
* an improved monitor (HELP key) - still not very good..
* configuration file instead of patch program
* bank switching implemented for later TELESTRAT compatibility
(at the moment, the "ATTELSTR" crashes at "disc access" during
booting :-( ). Requires another 128kBytes of your Atari memory..
* KeyPad ) to re-enable IRQ interrupt. Due to incomplete
VIA emulation, sometimes (e.g. starting ORICMON) the
cursor is "freezed" - only in that cases try ')' !!!
* one program both for 68000 or 68020+ machines
V0.5:
Internal version, never published. Last pure assembler version..
No real improvements, only a lot of tries to increase speed ..
V0.4:
As far as I remember just some bug fixes..
Some bad monitor was also installed.
Fastest version of ATORIC up to now..
V0.3:
ST Overscan support. ST-Monochrome monitor support (Uuugh..).
Some "faked" timer stuff for games. Tape routines
re-worked (after looking at the EUPHORIC method).
V0.2:
keyboard and tape emulation improved (not too much..).
Falcon030 RGB overscan (VGA of course has no need for that).
interrupt timing improved.
V0.1:
First public release. Already working..
Two versions for 68000 and 68020+ machines


The supplied programs
---------------------
DEFENDER:
For movement, use A and Z keys to move up or down, . and / for
left/right (users with german keyboard: set YZ_SCANTURN to 1,
use A and Y, , and . to move).
If you don't like the slow display speed of ATORIC, increase
LINES_VBL in the CFG file on your own risk. If your Atari
crashes and the screen refresh is still too slow, buy a faster
Atari..
CHESS-II:
Have fun.. Don't think you could understand the spoken chars-
the emulation speed is too slow (ST,Falcon,TT)
WELCOME:
A patched version of the original demonstration program for the
ORIC ATMOS. Patched because WELCOME gets the bytes from the cassette
instead of using the "normal" ATMOS-ROM-routines (ATORIC doesn't
handle byte-level cassette emulation).


What's on the "NET" regarding ORIC?
-----------------------------------
http://homepage.ensica.fr/oric/oric_english.html
http://homepage.ensica.fr/~frances/ # ORIC pages and EUPHORIC
http://ourworld.compuserve.com/homepages/laurentch/internet.htm # a good link page
http://wwwperso.hol.fr/~mpointie/ # DBug of NeXT - cool!
http://www.atari-computer.de/cpepper/ # news about ATORIC
ftp://ftp.tardis.ed.ac.uk/users/alexios/Oric # the great ftp server of Alexios

Just start at any of those WWW pages and you'll find the ORIC WEB RING
containing a lot of links about ORIC homepages..
If you like DEMOS don't miss DBUGs pages!


THANKS to:
----------
* Dr. Uwe Seimet:
He had the excellent idea how to write an efficient 6502 emulator
for the 68000. And he included the source code in his C64-emulator
package (1987).
* Fabrice Frances:
He is the main driving force of nearly all ORIC activities.
Knows everything about the ORIC hardware and gave lots of advice!
His PC-emulator EUPHORIC emulates an ORIC incredibly accurate!
* DBUG of NeXT (Mickael Pointier):
His ORIC demo programs just get the best out of the ORIC
(and sometimes show the limitations of ATORIC)
As a demo coder, he provided a lot of very good tips
for the screen emulation part.
(I didn't try out all of those tips up to now but I'll do :-( )
* Draco (Konrad M.Kokoszkiewicz):
Some very interesting discussions about 68030 optimization.
Visit his ATARI XL emulator (if you have a Falcon), for the
68030 he has the ultimate 6502-emulator!
* Jens Heitmann:
No ORIC fan but he installed ATORIC on his TT and gave
some good hints how to get it running on TT and under GEM.
* Matthias Jaap:
At least in the Atari community he is _the_ driving force
of the newer emulation scene. He organized the non-internet
distribution of ATORIC and ported an ORIC-BASIC to ASCII program.
* Alexios Chouchoulas:
Helped me to get in touch with the ORIC scene,
has set up the best software description WWW pages!
* Steffen Scharfe:
His article in ST Computer 4/1992 about overscan on Atari ST
made the "ORIC feeling" possible on the ST
* The various people who created the amazing ORIC PAGES on the WWW
* ..

That's all.
I'm quite sure that nobody will read that lot of text.
If you want to contact me, write an e-mail to:
(are there really only three people interested in ATORIC??)

Christian Peppermueller
cpepper@atari-computer.de

 
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